The measured top-quark width is

PHYSICS · Multi-part · Fermi University Physics · Particle Physics & Quantum Fields · Particles, interactions and experiment · Particles, interactions and experiment

Symmetry and Flavour, Ch Heavy flavour: charm and beauty decays and the magnitudes of the CKM elements

Problem

The measured top-quark width is Γt=1.42 GeV\Gamma_t = 1.42\,\mathrm{GeV}. A rough estimate of the time needed for coloured quarks to combine into a hadron is τhad∼ℏ/Λ\tau_{\rm had} \sim \hbar/\Lambda, with Λ≈0.3 GeV\Lambda \approx 0.3\,\mathrm{GeV} a typical strong-interaction energy scale. ((a)) Estimate the top-quark mean lifetime τt\tau_t. ((b)) Estimate τhad\tau_{\rm had}. ((c)) State, with the ratio of the two times, whether a top hadron can form before the top quark decays.

Browse the problem library